Homebrew PCBs

DJ Delorie wrote:
> "Herbert E. Plett" <cachureos@...> writes:
>> perhaps a little more HCl is needed, it also fumes out...
> 
> Follow-up:
> 
> CuCl concentration is below 1.2 (which I figured).
> 
> Acid seems high enough.  I heated some copper wire to get Copper
> Oxides, and the etchant dissolved that just fine, leaving a bright
> pinkish copper behind.  I did that a few times to get more copper into
> the tank, and then left the wire in there.  Perhaps by the time I get
> around to fiddling with it again it will be more usable, otherwise
> I'll put in more H2O2.
> 
> I did make up some NaOH solution for titration but it neeeds time to
> fully dissolve.
> 
NaOH should dissolve in < 10 minutes even in cold temperatures. Usually 
the heat generated speeds up the processes to under a minute.
Are you sure its NaOH ?
Does it spoon of NaOH power placed on exposed surface absorb water from 
the atmosphere in 1/2 day to a liquid ?
If not then it may be mostly Na2CO3